Update old posts

[matt-dray]

Updated old posts to remove name (now handled via YAML), add session info, spellcheck, add blank target links, add accessible images, usecurly braces around package names, general sentence improvements, added some additional material where necessary. Updated:

• Blogdown: change Lithium theme font-face (2018/11/29)
• Quantify colour with magick (2018/11/25)
• Waggle dance with ggbeeswarm and emoGG (2018/11/21)
• R training featuring Pokemon (2018/11/04)
• R session info info (2018/10/13)